Parasitism of algae by lignicolous Basidiomycota and other fungi

On water agar, 30 out of 81 species of fungi tested showed positive directional hyphal growth towards microcolonies of the green alga Protococcus sp. and produced coralloid masses of branched assimilative hyphae within the invaded algal colonies. Of 77 species of fungi tested against the blue-green alga Synechococcus elongatus, 33 exhibited this same phenomenon. Cell walls of S. elongatus were subsequently lysed while only cell death occurred in Protococcus sp., resulting in the release of the contents that were presumably absorbed by the coralloid hyphae. Branched hyphae from some invading fungi occasionally attached to larger individual cells of Protococcus sp., penetrated the walls, and absorbed the contents.